Greenland Ice Sheet Loses Ice for 30th Year Straight

The Greenland ice sheet losing ice for a thirtieth straight year is the kind of climate milestone that should stop your scroll. Scientists at the Danish Meteorological Institute say Greenland has now ended thirty consecutive annual cycles in the red, according to Carbon Brief, and the last year it gained ice was nineteen ninety-six.

What makes the streak so striking is that this was not a wild year. Greenland lost ice even though the summer started cool and the melt was modest, which tells you how tilted the whole system has become.

Greenland ice sheet loss, by the numbers

Over the twelve months to August twenty twenty-six, the world's second-largest ice sheet lost around one hundred thirty-five billion tonnes of ice. For the first time, the analysis also includes a second estimate that blends one climate model with weather stations, satellites, GPS and aircraft observations. That approach puts the loss even higher, at about one hundred seventy-three billion tonnes.

Scientists use different methods because nobody has perfect information about how thick the ice is, how fast it flows or how quickly it melts at the surface. Both estimates point in the same direction, and that direction is down.

Why thirty years is the magic number

Climate researchers usually need about three decades of data to separate the fingerprint of human-caused warming from normal weather swings. A single scorching summer or a snowy winter can mislead, but thirty years in a row cannot.

The authors, Martin Stendel and Ruth Mottram, note that the ice budget has ended negative in warm years, cold years and snowy years alike. The biggest single-year loss remains twenty twelve, when roughly four hundred fifty-eight billion tonnes vanished. Even the last two quiet years each lost more than one hundred billion tonnes.

A cool summer still could not save it

The winter was unusually dry in southern Greenland, leaving around forty billion tonnes less snow than normal. Then a cool, cloudy start to summer delayed the melt season until the fifth of June, nine days later than the long-term average.

Warm, sunny weather arrived at the end of June, and on the twenty-second of July melting covered about seventy-five percent of the ice sheet. For comparison, July twenty twenty-five holds the record, with more than eighty-one percent melting at once.

Part of the reason Greenland dodged a worse year was luck with the jet stream. Heatwaves baked southern Europe and North America under an Omega-shaped pattern, which left Greenland on the cool, wet side. Had that pattern shifted by half a wavelength, the authors say, record melt was likely.

The Petermann ice island

The most dramatic loss happened at the edges. On the fourth of August, a tabular iceberg more than seventy-six square kilometres in size and about one hundred fifty metres thick broke off the Petermann glacier in north-west Greenland. Carbon Brief says that is enough frozen water to submerge greater London under roughly six and a half metres.

It was the biggest calving event by any Arctic glacier since twenty twenty. Two more ice islands are expected to detach, and together the three would remove around twenty-two percent of Petermann's remaining floating ice. Floating ice does not raise sea levels directly, but these glaciers act like a brake on ice flowing off the land.

Why Antarctica is the real worry

A new assessment known as IMBIE, published in the journal Scientific Data, found that Greenland and Antarctica together lost more than eleven thousand billion tonnes of ice between nineteen seventy-nine and twenty twenty-three. That raised global sea levels by around thirty-two millimetres and now accounts for almost a quarter of observed sea level rise.

Researchers describe a "Greenlandification" of Antarctica, meaning the melt, shrinking sea ice and retreating glaciers seen in Greenland for decades are now showing up in the far bigger southern ice sheet. Antarctica holds roughly ten times more ice, so the stakes for coastal cities are huge.

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